March 12, 2015 – A 93-second thruster burst on March 10 slightly adjusted the New Horizons spacecraft’s trajectory toward Pluto. The shift was based on the latest orbit predictions of Pluto and its largest moon Charon, estimated from various sources, including optical-navigation images of the Pluto system taken by New Horizons in January and February.
This first maneuver of New Horizons’ approach phase to Pluto was planned to slow the spacecraft’s velocity by just 1.14 meters per second – barely a tap on the brakes for a probe moving about 14.5 kilometers per second – and moved its July 14 arrival time back on schedule with a change from the pre-burn course of 14 minutes and 30 seconds. It will also shift the course “sideways” (if looking from Earth) by 3,442 kilometers (2,139 miles) by July 14, sending the spacecraft toward a desired flyby close-approach target point.
Using commands transmitted to the spacecraft on March 8, the thrusters began firing at 3:15 a.m. MDT, and stopped just 93 seconds later.
Initial telemetry indicating the spacecraft was healthy and fired on command reached the New Horizons Mission Operations Center at APL through NASA’s Deep Space Network at 10 a.m. MDT.
APL manages the New Horizons mission for NASA’s Science Mission Directorate in Washington. Alan Stern, of Southwest Research Institute (SwRI) in Boulder, is the principal investigator and leads the mission. SwRI leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. APL designed, built and operates the spacecraft. The Laboratory for Atmospheric and Space Physics at CU-Boulder contributed the Student Dust Counter, the first student built instrument to ever fly on a NASA planetary mission.
Trajectory Correction Maneuver 15B2
Result: slowed New Horizons velocity by 1.14 meters/second; delayed Pluto arrival time by 14 minutes 30 seconds; shifted trajectory toward desired flyby close-approach point.
New Horizons approximate distance from Earth: 3 billion miles; 4.8 billion kilometers (32.28 astronomical units)
New Horizons approximate distance from Pluto: 93 million miles; 149 million kilometers (1 AU)
Time for signal to reach Earth: 4 hours, 28 minutes, 31 seconds
Primary communications: NASA Deep Space Network Canberra Station, Australia (70-meter antenna)
Fast Fact: After the maneuver New Horizons entered “spin mode” – a more efficient mode for sending data back to Earth – where it will remain until April 4.